The overall objective of this Core is to develop and apply multi-nuclear magnetic resonance (NMR) spectroscopy and imaging core facilities for the study of hypoxic-ischemic brain damage in developing rats. The spectroscopy component of the Core will apply MR spectroscopy techniques to evaluate metabolic alterations which occur during and following cerebral hypoxia-ischemia in developing rats. Spatially localized 31P and 1H MR spectroscopy will be used to quantitate changes in energy metabolism, lactate concentrations, intracellular pH, and free cytosolic magnesium concentrations. The imaging component of the Core will continue to develop and apply magnetic resonance imaging (MRI) techniques to evaluate perinatal hypoxic-ischemic brain damage. Two imaging techniques will continue tobe used to elucidate the sites and severities of brain damage at different stages of hypoxia-ischemia and recovery. These techniques include diffusion and T2-weighted spin echo imaging. Our previous results have indicated that diffusion imaging is a sensitive method for early detection of hypoxic-ischemic injury, while T2-weighted spin echo imaging more accurately monitors long-term damage. Animal movement and multi- animal devices essential for obtaining reliable images will be continually designed, constructed and refined. These devices will be incorporated into the general probe design for spectroscopy and imaging.